Season both sides of the chicken breasts with the salt and pepper. Place chicken breasts on a hot grill sprayed with some of the vegetable oil. Turn chicken every 3 or 4 minutes and cook just until firm but not dried out.

In a separate pan, saute the onion and garlic until onion is translucent. Do not let garlic brown. Add the chanterelles and marjoram; lightly saute. Season with salt and pepper. Add the sherry to pan and bring to a simmer as you stir and scrape up all cooked-on bits of food. Continue cooking until liquid has reduced by half. Whisk in the softened butter, a little at a time, until well-combined. Check seasoning and keep sauce warm until needed.

To serve, slice chicken breasts and fan out slices. Top with chanterelle-butter sauce. Makes 6 servings.